Apple investors are worried about the iPhone sales.
Business Insider reports the worry is over signs that Apple's revenue could be as much as 7% lower than the company's expectations.
Apple blames slowing iPhone sales in China and other developing markets.
A survey shows that there are some big reasons why people aren't upgrading the United States, including price and a lack of new features.
17% of those surveyed said their phones worked just fine and they did not feel the need to upgrade.
13% said the newer phones are "too expensive."

According to a report by Digital Trends, Amazon is finally going to allow iOS users to control their digital assistant, Alexa, with their voice. Users will reportedly be able to open up the Alexa app and ask Alexa questions, however they won't be able to use Alexa native on iOS, as Apple still doesn't allow third-party digital assistants to receive the same treatment as Siri. Digital Trends reports that the move to Android and iOS indicates Amazon's big push into third-party operating systems. The update is reportedly expected to be rolled out over the next few days